Engine stopped. Assumed failed fuel pump. Replacement?

So my 1600 kombi engine stopped last week. Symptoms were just like when you turn the fuel off on the old lawn mowers and let them run dry. I knew I had plenty in the tank but went through everything ignition related and all checked out ok. So on to the fuel side. Minimal fuel in the lines and not much coming out when engine cranked over. I primed it using a fuel bulb and it fired up immediately. Hence my assumption the fuel pump is dickey.

Several questions.

I'm running twin kadrons. Is the stock style pump enough or should I be upgrading to electric straight up?

I see 2 styles of pump, one listed as being for generator models and one for alternator models. What's the difference? Is it simply pipe placement or something else?

The pushrod that operates the pump is supposed to have a max height of 13mm but mine seems to be half that. The book says you add or remove gaskets to get it right but there certainly aren't 6mm of gaskets there and the rod doesn't look appreciably worn. Is the quoted figure right and if so what would cause mine to come up short? Wrong rod?

Should I just go electric to start with?

Hi mate, I have had a stock style fuel pump on my 1916 for years feeding twin Kaddies, nothing wrong with that. I believe the alternator pumps were tilted slightly. Not sure on the pushrod lengths though sorry mate. Electric pumps can be a pain on Kads as they aren't a fan of higher than 2-3 psi fuel pressures. Lots of aftermarket fuel pressure regulators don't go that low.

Alternator pumps are off to the side a little and run a shorter rod. Can't remember how much.

I've looked further into this and found that some pumps have a protruding actuator with short rod and others have a longer rod with flush actuator. My engine has a flush actuator and shorter rod which sounds like the wrong combo was used. Not sure how it managed to work at all.

My rod is 100mm and looks to be about 6-8mm too short to do much. The longer rod is apparently 108mm or so.

Off to parts suppliers at lunchtime to try and get a new pump.